The Mary the Catholics worship (or, "venerate" as they like to say), is in reality the evolution of the goddess of cultures the Romans had conquered.
Veneration and worship are completely different. Veneration is just admiring or looking up to, while worship takes that to a much higher level. Mary could not live without God, she had no part in creating the universe. God CREATED Mary, and her life depends on Him. If one of us is wrong, God will forgive us when our death comes